I planted many coneflower seeds and zinnia seeds in late April, and the area is now smothered with wild “weeds” (especially forget-me-nots, copperleaf) with no sign of the planted seedlings. Have they been smothered? Planted too late for this year, could come up later – seems kind of late with nothing above ground, bad seeds (McKenzie)?
How unfortunate! Zinnia seedlings usually appear within a week of seeding so if you have no signs of them now, those seeds have failed or, as you suspect, the tiny seedlings were overwhelmed by weeds.
If the seeds were new this year, I doubt that they were the problem. McKenzie is a reliable supplier.
The good news is that you could still sow Zinnia seeds through June. I would recommend you clear the area completely, getting rid of all those weeds, and try the Zinnias again. You can seed some right away and another batch a week later, to extend the bloom period.
But before seeding, make sure the conditions are right. Does the area get full sun? Is the soil friable (crumbles easily in your hand)? Did you add some organic matter to the bed? Make sure the seed bed is moist throughout the germination period. Do not let it dry out, but do water gently to avoid washing the seeds away. Zinnias are drought tolerant but must be watered regularly for a month or so, while they are getting established.
Here’s our Gardening Guide on Drought Tolerant Annuals, which provides good advice on growing the plants and provides lists of other plants you might like to add to the bed.
If you would like to try the coneflowers again next year, here is our Gardening Guide on Long Blooming Perennials.
They require some special attention to germinate.
As we explained to another inquirer, “Purple coneflowers require exposure to cold conditions for a period of time in order to break their dormancy (called cold stratification). This can be achieved by planting the seeds directly in the ground in the late fall so the seed overwinters and germinates naturally in the spring. This can also be achieved indoors by keeping the seed in a slightly moistened soil-less potting mix in a plastic bag and alternating between the fridge and freezer for a week. Click here for the detailed instructions on this method from Wildflower Farm.”
Good luck with your flowerbed!
June 15, 2024